Hollow conductor roll

ABSTRACT

A hollow conductor roll is used in electrical zinc plating, the outer surface of which is made of middle carbon steel and hard metal plating, and the inner surface of which is made of pure metal with low hardness and good electric conductivity. The hard outer metal plating renders the roll less susceptible to damage thereby reducing production cost and the hollow roll is relatively easy to cool by passing cooling liquid therethrough.

United States Patent Hatagi et a].

[4s] July 18, 1972 154] HOLLOW CONDUCTOR ROLL [72] Inventors: Hlroyuldl-htagl; Kenlchl Kanamaru; Yauo Funuaki, all of Fukuyama shi,

Japan [73] Assignee: Nippon Kolum Kabushlki Kahlua, Tokyo,

Japan [22] Filed: Oct. 14, 1968 [21] Appl.No.: 767,419

521 U.S.Cl. ..l9lIlA,204/279 [51] met. ..n01k3/o0 5sFleldolSearch.............................l9l/lA;204/279, 25

[5 6] References Cited UNITED STATES PATENTS 2,687,699 8/1954 Oakes..165/89 UX COOLING LIQUID 2,266,347 12/1941 Watson ..l91/l A 2,526,31210/1950 Winterhalter. ....l91/l A 2,958,742 11/1960 Palmer ..l9l/1 APrimary Bummer-Arthur L. La Point Assistant Examiner-George H. LibmanAttorney-Robert D. Flynn [57] ABSTRACT A hollow conductor roll is usedin electrical zinc plating, the outer surface of which is made of middlecarbon steel and hard metal plating, and the inner surface of which ismade of pure metal with low hardness and good electric conductivity. Thehard outer metal plating renders the roll less susceptible to damagethereby reducing production cost and the hollow roll is relatively easyto cool by passing cooling liquid therethrough.

10 Claims, 1 Drawlngfigure PATENTEDJUUMTZ 3.678.226

COOLING l4 LIQUID nouow CONDUCTOR ROLL This invention relates to aconductor roll to be employed. for example, in electrical zinc plating,and rrrore particularly to a conductor roll for conducting an extremelyhigh current at a comparatively low voltage.

When a metal strip is continuously n'nc plated electrically, a conductorroll is brought into contact with the metal strip. The roll is driven bya suitable driving device to be rotated at an equivalent peripheralspeed as the speed of the metal strip moving through the system, andconducts the plating current through the metal strip to an oumidecircuit. A plating current of about 16,000 amperes, at about 18 volts ispassed through this conductor roll.

Heretot'ore, such conductor rolls have been solid structures made ofpure nickel or copper. However, such a solid roll made of pure metalssuch as nickel or copper for obtaining high electrical conductivity, hasa comparatively low hardness, which renders the roll highly susceptibleto mechanical damage. Due to the high cost of materials and labor, theseprior art conductor rolls are uneconomical.

Furthermore, it is difficult to cool these solid conductor rolls when alarge quantity of heat is created therein. These and other disadvantageshave constituted almost unavoidable drawbacks of the conventionalconductor rolls.

Therefore, the main object of the present invention is to provide aconductor roll which is mechanically strong, has a good electricalconductivity, and is economical to manufacture.

it is a further object of this invention to provide a conductor rollwhich is relatively easy to cool.

According to this invention, a hollow roll shaft member is provided oneach side of the conductor roll and is made of a metal having a highelectrical conductivity. A roll sleeve member is provided on each sideof the conductor roll and is tightly fit on the outside surface of atleast a portion of the roll shaft. A hollow roll body is connected tothe roll sleeve at each end thereof by means of coupling members whichconnect the inner surface of the roll body to the roll sleeves. Thehollow roll body has a hard metal layer on the outside surface thereofand a lining made from a metal having a high electrical conductivity onat least a portion of due inside surface thereof. Further provided is aconnecting member interconnecting the high conductivity metal lining tothe roll shafts.

The invention will be better understood from the following detaileddescription taken in conjunction with the accomanying drawing whichillustrates a sectional view of a preferred embodiment thereof.

In the drawing, a roll shalt l of hollow construction is made of 99.9percent pure copper and a roll sleeve 2 made of general structural steelis tightly fit on the outer surface of the roll shaft 1. Couplingmembers 3, 3' connect the roll sleeve 2 to a roll body 4 of hollowconstruction to join together all of the members I through 4 to form anintegrated conductor roll. The roll body 4 is made of a medium carbonsteel for machine structure, and the coupling members 3, 3 are made ofan ordinary structural rolled steel. All of the junctions between thecoupling members 3, 3' and the roll body 4 and between the couplingmembers 3, 3' and the roll sleeve 2 are welded together. The peripheralsurface of the roll body 4 is electrically plated with a hard chromiumlayer 5, and the inside surface of the roll body 4 is provided with alining 6 consisting of about 5 mm thickness of 99.9 percent pure copper.This copper lining 6 is brazed to the inner end of the copper roll shaft1 by means of an intennediate connecting number '7.

A source of cooling liquid 14 is connected to hollow roll shaft 1 forpassing a cooling liquid therethrough. Complementary apparatus (notshown) is provided at the other end (not shown) of the conductor rollassembly. This cooling apparatus is of a well known type and is notdescribed herein in more detail. lts operation should be apparent tothose ordinarily skilled in the art.

Although the drawing illustrates merely the left side halfof (notshown)hmasirnilarconstructionasthelefisidehalf. Further provided is aconductor ring 8 and brushes 9 contactingtheconductor roll on theouterendofthe copper roll shaft for conducting the current passing throughthe strip being plated to leads 10. A portion ll of sleeve 2 isjoumalled on a bearing(notshown) inamannerwell knownintheartand l2 and13 designate hollow spaces inside the roll shaft 1 and the roll body 4,respectively.

When the conductor roll according to the present invention is used in anelectrical plating system, the electric current flowing through themetal strip (not show) to be plated is at first through the hardchromium plated layer 5 on the hollow roll main body 4, then through theroll main body 4, and thereafter through the inner conductive lininglayer 6. The current then through connecting member 7, roll shaft 1,conductor ring 8, brushes 9, and a group of conductor leads l0,toabm-bar (not shown).

As described above, the conductor roll according to the presentinvention is so constructed that the outside peripheral portions whichcontact the strip to be plated and which are subject to mechanicaldamage, are made of medium class carbon steel having a hard outerchromium plated layer 5 thereon. The irside portion of the roll isprovided with a lining 6 of a lower hardness pure metal having a goodelectrical conductivity. Thus, a conductor roll of superior qualityresults which has a higher resistance to outside physical damage thanthe conventional solid conductor rolls made of pure metal, and anequivalent electrical conductivity to the conventional rolls. The rollsaccording to this invention are economical to manufacture, requiringonly about one-fourth of the cost of the conventional rolls because ofthe hollow roll shaft 1 and the roll body 4 which is made of relativelyinexpensive steel.

Further, since it is easy to flow a cooling liquid such as water throughthe hollow spaces l2, 13 within the roll shaft and the roll body,respectively, heat created in the conductive roll may be removed in asimple and inexpensive manner.

What is claimed is:

1. A fluid cooled conductor roll comprising:

a hollow roll body (4) having a hard metal layer (5) on the outsidesurface thereof and a lining (6) made from a metal having a highelectrical conductivity bonded on at least a portion of the innersurface thereof;

a hollow roll shaft member (1) made of a metal having a high electricalconductivity, at least a portion of said roll shaft member (1) extendinginto the hollow portion of said hollow roll body (4);

a roll sleeve member (2) tightly fit on the outside surface of atleastaportionofsaidrollshafi (1);

coupling members (3, 3') connecting an end of the inner surface of saidroll body (4) to said roll sleeve member (2), said coupling members (3,3') being spaced from each other and being welded to said roll body (4)and to said roll sleeve member (2); and

a connecting member (7) interconnecting said high conductivity metallining (6) to said roll shaft member (1) only adjacent an end of saidhollow roll body (4) so that said hollow roll body (4) has no radialobstructions in the central portions thereof, thereby providing animproved coolant flow path therethrough.

2. A conductor roll according to claim 1 wherein said hollow roll shaftmember (1) extends only partially into the hollow portion of said hollowroll body (4) so that said hollow roll body (4) has no obstructions inthe central portions thereof.

3. A conductor roll according to claim 2 wherein said hollow roll shaftmember (1) extends into the hollow portion of said hollow roll body (4)only to said connecting member (7).

4. A conductor roll according to claim 1 wherein said hard metal layer(5) is an electrically plated hard metal layer.

5. A conductor roll according to claim 1 wherein said hard metal layer5) is a chromium layer.

6. A conductor roll according to claim 1 wherein said lining (6) is alayer of substantially pure copper.

7. A conductor roll according to claim 1 wherein said lining theconductor roll, the right side half of the conductor roll (6)isbrazedtothe inner surface of said hollow roll body(4).

8. A conductor roll according to claim 1 further comprising a ring andbrush assembly (8,9) mounted on an end ofsaid roll shaft member (1) toconduct electric current from said conductor roll.

9. A conductor roll according to claim 1 wherein said hollow portionsofsaid roll shah member (I) and ofsaid roll body i I i l

1. A fluid cooled conductor roll comprising: a hollow roll body (4)having a hard metal layer (5) on the outside surface thereof and alining (6) made from a metal having a high electrical conductivitybonded on at least a portion of the inner surface thereof; a hollow rollshaft member (1) made of a metal having a high electrical conductivity,at least a portion of said roll shaft member (1) extending into thehollow portion of said hollow roll body (4); a roll sleeve member (2)tightly fit on the outside surface of at least a portion of said rollshaft (1); couplinG members (3, 3'') connecting an end of the innersurface of said roll body (4) to said roll sleeve member (2), saidcoupling members (3, 3'') being spaced from each other and being weldedto said roll body (4) and to said roll sleeve member (2); and aconnecting member (7) interconnecting said high conductivity metallining (6) to said roll shaft member (1) only adjacent an end of saidhollow roll body (4) so that said hollow roll body (4) has no radialobstructions in the central portions thereof, thereby providing animproved coolant flow path therethrough.
 2. A conductor roll accordingto claim 1 wherein said hollow roll shaft member (1) extends onlypartially into the hollow portion of said hollow roll body (4) so thatsaid hollow roll body (4) has no obstructions in the central portionsthereof.
 3. A conductor roll according to claim 2 wherein said hollowroll shaft member (1) extends into the hollow portion of said hollowroll body (4) only to said connecting member (7).
 4. A conductor rollaccording to claim 1 wherein said hard metal layer (5) is anelectrically plated hard metal layer.
 5. A conductor roll according toclaim 1 wherein said hard metal layer (5) is a chromium layer.
 6. Aconductor roll according to claim 1 wherein said lining (6) is a layerof substantially pure copper.
 7. A conductor roll according to claim 1wherein said lining (6) is brazed to the inner surface of said hollowroll body (4).
 8. A conductor roll according to claim 1 furthercomprising a ring and brush assembly (8,9) mounted on an end of saidroll shaft member (1) to conduct electric current from said conductorroll.
 9. A conductor roll according to claim 1 wherein said hollowportions of said roll shaft member (1) and of said roll body (4) are incommunication.
 10. A conductor roll according to claim 9 furthercomprising cooling means (14) coupled to said hollow roll shaft member(1) for passing a cooling liquid through said shaft member (1) andthrough said hollow roll body (4).